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Number of results: 9
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Abstract

Mining wastes are by-products generated during search, excavation and processing, both physical and chemical, of ores and other minerals. In 2017, wastes from group 01 constituted 60% of total wastes produced in Poland. According to the statistical data, approximately 92% of the waste generated during the excavation and processing of hard coal is economically reused. 30% of this waste used in industry and nearly 70% is used for the reclamation of the degraded industrial areas. At present, there is a tendency in the E uropean Union to shift from a linear economy to the Circular E conomy. The goal is to maintain economical value of the resources, among others, by their reuse in a productive way, which at the same time eliminates waste. One of the industrial branch where the ideals of a Circular E conomy can be implemented is the mining industry. Mining wastes may form one of the sources of anthropogenic minerals, as they belong to alternative aggregates. Deposits of anthropogenic minerals are considered sources of valuable raw materials which guarantee that the products made on their basis will be of high quality. The article presents the results of physico-chemical tests, the leachability of contaminations and phytotoxicity tests carried out on the basis of the selected mining waste in light of a Circular E conomy.

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Authors and Affiliations

Monika Czop
Amanda Kościelna
Karolina Żydek
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Abstract

The objective of this study was to investigate combustion characteristics of biomass (willow, Salix viminalis) burnt in air and O2/CO2mixtures in a circulating fluidized bed (CFB). Air and oxy-combustion characteristics of wooden biomass in CFB were supplemented by the thermogravimetric and differential thermal analyses (TGA/DTA). The results of conducted CFB and TGA tests show that the composition of the oxidizing atmosphere strongly influences the combustion process of biomass fuels. Replacing N2in the combustion environment by CO2caused slight delay (higher ignition temperature and lower maximum mass loss rate) in the combustion of wooden biomass. The combustion process in O2/CO2mixtures at 30% and 40% O2is faster and shorter than that at lower O2concentrations.

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Authors and Affiliations

Monika Kosowska-Golachowska
Agnieszka Kijo-Kleczkowska
Adam Luckos
Krzysztof Wolski
Tomasz Musiał
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Abstract

The article aims to show literary images of skomorokh in the Russian versions of Christian‑Jewish disputes over faith. A textological analysis of 13 manuscript copies of Тhe Tale of the Christian and Jewish faith from the 17th‑19th centuries allows us to show how the image of the skomorokh changed in manuscripts of the Short redaction, the Extensive redaction, and the Unique redaction.
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Authors and Affiliations

Eliza Małek
1

  1. Uniwersytet Łódzki
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Abstract

This paper presents a geeral concept of an adjustment method Edgeworth series applied. The author proposes to replace distributions with approximating functions representd by Edgeworth series, which would be a universal, probabilistic model of the adjustment problem. Special attention is paid to variance an lysis. A con variance matrix C, of the vector X, its estimate C,, and and estimate of the variance coefficient a0 are derived. Also some further properties of the proposed method are presented.
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Authors and Affiliations

Andrzej Dumalski
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Abstract

The study presents the critical evaluation of existing drainage systems from legal, eco-nomical, environmental and technical viewpoints. Nearly 80% of agricultural land in Lithuania drained by underground drainage systems covers around 3 million hectares. The prevailing large scale drainage systems with a complex of engineering structures such as conducting ditches, drains and collectors, local roads, bridges or farm road-crossings, dikes, dams, water reservoirs, pumping stations for irrigation and for drainage need today an efficient management solution in a new economic situation. The detailed analysis of legal and economic instruments adopted in transferring the management responsibilities of drainage systems to users has been carried out. The study resulted in a number of practical contributions towards the amendments in the Law on Land Reclamation in Lithuania and the establishment of a system of indicators that would allow rationalisation of subsidy allocations for the maintenance and improvement of the drainage systems. These subsidies from the state budget make at the moment the largest share among the investment sources. The financial and in kind contribution of drainage users is permanently increasing as are the allocations of the structural funds for public projects. The EU pre-accession programme SAPARD started in 2000 has supported some investments in rural areas. Unfortunately, it did not support the drainage infrastructure properly. A critical review of previous measures allowed suggesting new actions within the framework of the actual support from EU structural funds.

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Authors and Affiliations

Antanas Maziliauskas
Vytautas Morkunas
Zenonas Rimkus
Valentinas Šaulys
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Abstract

The surfacing layer of cobalt-based alloy is prepared using the tungsten inert gas welding (TIG) process and employing the UMCo50, ST1 and ST6 filler materials. The metallographic testing, hardness, wear and corrosion testing of different surfacing layers have been carried out. Each area of the surfacing layer is characterized using the optical and scanning electron microscope (SEM). Cellular and a few columnar dendrites have been observed near the fusion line of the UMCo50 surfacing layer, and cellular structure is observed in the central region. Dendrites and cellular crystals have been observed in the ST1 and ST6 surfacing layers. The average hardness of UMCo50, ST1 and ST6 surfacing layers are 320 HV, 672.3 HV and 497.5 HV, respectively. The wear loss of the ST1, ST6 and UMCo50 surfacing layer is 2.71 mg, 4.35 mg, and 14.57 mg, respectively. The corrosion weight loss of the ST1, ST6 and UMCo50 surfacing layers are 0.0388 g, 0.0477 g and 0.0833 g, respectively.
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Authors and Affiliations

Haitao Xue
1
ORCID: ORCID
Xiaoping Luan
1
ORCID: ORCID
Weibing Guo
1
ORCID: ORCID
Dong Zhou
1
ORCID: ORCID

  1. Hebei University of Technology, School of Materials Science and Engineering, No. 5340, Xipingdao Road, Beichen District, Tianjin, 300401, PR China
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Abstract

Is this article simulation of statistical measurements is performed on the basis of which the analysis of the standard deviation of the obtained results is carried out. It is shown that the standard deviation is minimum and independent from measurement duration while an object is in the state of equilibrium. For objects in a stationary non-equilibrium state the standard deviation depends on the duration measurements and the parameters of the state. The influence of these factors on the standard deviation is assessed with equation which includes the relaxation time. The value of the relaxation time is determined by approximating the energy spectrum of the studied signals. The analysis of energy spectra showed that the spectrum of white noise is inherent in objects in equilibrium; the flicker component of the spectrum occurs when the state of the object deviates from equilibrium.
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Authors and Affiliations

Krzysztof Przystupa
1
Zenoviy Kolodiy
2
Svyatoslav Yatsyshyn
2
Jacek Majewski
3
Yuriy Khoma
2
Iryna Petrovska
2
Serhiy Lasarenko
2
Taras Hut
2

  1. Department Automation, Lublin University of Technology, ul. Nadbystrzycka 36, 20-618 Lublin, Poland
  2. Lviv Polytechnic National University, Institute of Computer Technologies, Automatics and Metrology, S. Bandera Str. 28a, 79013, Lviv, Ukraine
  3. Department of Automation and Metrology, Lublin University of Technology, ul. Nadbystrzycka 38D, 20-618 Lublin, Poland
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Abstract

RNA extraction involves several main stages, regardless of the method of extraction: homogenization, effective denaturation of proteins from RNA, inactivation of ribonuclease and removal of any DNA, protein, and some residual contamination. Isolation of undamaged intact RNA is challenging when the related tissue contains high levels of polysaccharides and phenols. Several efforts have been made towards the comparison and optimization of extraction and purification methods for RNA from plant tissues. This is dictated by the necessity of obtaining RNA of a good quality and in a sufficient quantity for further molecular analyzes. Plant storage organs (such as bulbs or seeds) rich in polysaccharide and polyphenolic compounds present distinct challenges for total RNA isolation. Such components, considered in this case as contamination, may bind and co-precipitate with nucleic acids and negatively affect later assays. Since standard routine protocols yield unacceptable results in bulbs, we have designed a new method for RNA extraction. We used two modified procedures (based on CTAB and sarkosyl reagents) of RNA extraction from so called “difficult plant material” and compared them to a popular RNA isolation base on the column isolation kit and TriPure reagent. Our modified protocols dealt with problems of both RNA degradation and low yield caused by co-purification with polysaccharides present in plant bulbs. In this study we have shown that improvement of the CTAB and sarkosyl method with a lyophilization step of plant tissues leads to isolation of high quality RNA from difficult material like storage organs of bulbous plants. The main changes in the procedure compared to the previously described methods concerned the different order of lithium chloride and sodium acetate addition, lithium chloride concentration increase and modification of centrifugation conditions. Gel electrophoresis and spectrophotometer analysis confirmed the high quality and integrity of the obtained RNA. The modified procedures allowed for obtaining a satisfying amount of RNA concentration in the range from 280 to 950 ng/μl depending on the plant species. Thus, the demonstrated RNA isolation methods are efficient and can be used for plant material rich in polysaccharides, such as bulbs.

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Authors and Affiliations

Maria Duszyn
Brygida Świeżawska
Mateusz Kwiatkowski
Krzysztof Jaworski
Adriana Szmidt-Jaworska
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Abstract

In the 1980/1981 breeding season nesting of 9762 pairs of Pygoscelis papua, 59356 pairs of P. adeliae, 302388 pairs of P. antarctica and 1 pair of Eudyptes chrysolophus was observed in the region of King George Island. The greater part of P. antarctica rookeries was located in the hitherto unexplored cliffy coast in the northern part of the island. A hypothesis was set forth that the recent increase in penguin populations was mainly due to the retreat of glaciers and consequently the exposure of new places suitable for breeding sites.

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Authors and Affiliations

Bolesław Jabłoński

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